On November 13, 1811, in the middle of the War of Independence, the castle walls were the scene of the shooting of the famous guerrilla known as Uncle Camuñas. The French troops are also blamed for the deterioration of part of the porticoes of the fortress, damage that was later described by José María Quadrado in 1853 and, a few years later, by Carvajal y Rueda in 1857.

The great promoter of its recovery was Eugenia de Guzmán, better known as the Empress Eugenia de Montijo and heiress of the house of Villena. From 1857 she undertook an ambitious restoration with the aim of restoring the castle to its former splendor. While the exterior defenses were restored with fidelity to the original project, the interior reflected the aesthetic taste of the time. The architect Alejandro Sureda closed the galleries overlooking the courtyard using brick and adopting a neo-Gothic style. However, with the fall of the Second French Empire in 1870, the works came to a standstill, after the empress had invested more than a million and a half reales in the project, according to Torres Mena in Noticias conquenses.

Between 1881 and 1885, the castle was occupied by French Dominicans who adapted it as a monastery. Later, Hernando Fitz-James Stuart y Falcó, Duke of Peñaranda and grandnephew of the empress, resumed some restoration work and even lived in the fortress.

On June 3, 1931, the building was included in the National Artistic Treasure, a figure equivalent to the current Asset of Cultural Interest. Throughout the 20th century, the castle was put to various uses: it was used as a prison for the judicial district of Belmonte, later as a command academy for the Frente de Juventudes, and after that it fell into a period of semi-abandonment that aggravated its deterioration.

In the last decades, both in the 20th and 21st centuries, the fortress suffered new ravages until it was left in a worrying state of conservation. However, the property - which still belongs to the ducal house of Peñaranda, descendants of the Duchess of Alba María Francisca de Sales Portocarrero, sister of Eugenia de Montijo -, in collaboration with the town council of Belmonte and the Ministry of Public Works, promoted an ambitious rehabilitation plan. Thanks to this, the castle was able to open its doors to the public in the summer of 2010. A second phase of restoration was completed in 2017, allowing the monument to be consolidated as one of the great heritage references of Castilla-La Mancha.